Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f6482934473ad37…

MALICIOUS

PDF

80.2 KB Created: 2021-04-07 00:15:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 6aa987ca054bc4be6d24dccb292de44d SHA-1: 1ab44af537491b0e3e630cd6174640bd6b3e7273 SHA-256: 8f6482934473ad37559415be77281c3d8d9d05bc4040f7c8bc0fa4314677b956
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://cicatsalud.com/html/sites/default/files/webform/bulurifabisiwotubavigivos.pdf In PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/35757612566.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/pulipalukegibivep.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/40110328039.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/tizagoge.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/60015669747.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/42282539280.pdfIn PDF document text
    • https://www.visitsavannah.com/sites/default/files/webform/nodarinit.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/nuzutigurazuleziwuta.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/6669476875.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/nakevatekiviva.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/doxuwekuwazomiloxeri.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/65000750087.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=paralisis+nervio+facial+pdfPDF link annotation
    • https://drones.princeton.edu/system/files/webform/vijebutipide.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/61431168480.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/98562832035.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f8fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8FC 5208 bytes
SHA-256: af663b79453b1e147f190a3aa6e7e054b145a635011005b8f5738ace7168cb4a
font_01_sfnt_off00010acd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ACD 12188 bytes
SHA-256: 79d5b1d9ed305c3d6f6d2232dd0a1782a4495701ce0d1653c17eb9de1c02ecb4